One vertex per element, one color per generator, with an edge from x to x·s.
(2,5)(3,7)(9,10,14,15)(11,19,20,16)(12,17,22,21)(13,23,24,18)(25,26)(27,30)(28,33)(29,34)(31,35)(32,38)(36,37)(39,40)(1,2,6,5)(3,8,7,4)(10,15)(12,22)(16,19)(18,23)(25,27,31,38)(26,32,35,30)(28,36,34,40)(29,37,33,39)(1,3)(2,4)(5,8)(6,7)(10,15)(11,20)(12,22)(13,24)(25,28,31,34)(26,33,35,29)(27,36,38,40)(30,37,32,39)(1,2,6,5)(3,4,7,8)(9,11,14,20)(10,16,15,19)(12,23,22,18)(13,21,24,17)(25,28)(26,29)(27,36)(30,39)(31,34)(32,37)(33,35)(38,40)(1,4,6,8)(2,7,5,3)(9,12)(10,17)(11,18)(13,19)(14,22)(15,21)(16,24)(20,23)(25,29)(26,34)(27,37)(28,35)(30,36)(31,33)(32,40)(38,39)(1,5,6,2)(3,8,7,4)(9,13,14,24)(10,18,15,23)(11,21,20,17)(12,19,22,16)(25,30)(26,27)(28,39)(29,36)(31,32)(33,40)(34,37)(35,38)A Cayley diagram is a choice, not a fact about the group. Another drawing of this group — in a book, or on a different generating set — may look nothing like this one.